Rolling contact bearings and design procedureJashavant singh
this slide will give you idea about the rolling contact bearing , its types application areas and also you will learn how to design rolling contact bearing ,
comparison between the rolling contact and sliding contact bearing , advantage and disadvantages.
Rolling contact bearings and design procedureJashavant singh
this slide will give you idea about the rolling contact bearing , its types application areas and also you will learn how to design rolling contact bearing ,
comparison between the rolling contact and sliding contact bearing , advantage and disadvantages.
Rolling Contact Bearing, Selection of Rolling Contact Bearings, Machine Element Design, Bantalan Gelinding, Pemilihan Bantalan Gelinding, Perancangan Elemen Mesin
Rolling Contact Bearing, Selection of Rolling Contact Bearings, Machine Element Design, Bantalan Gelinding, Pemilihan Bantalan Gelinding, Perancangan Elemen Mesin
UNIT-4-ENERGY STORING ELEMENTS AND ENGINE COMPONENTS.pptxkarthi keyan
ENERGY STORING ELEMENTS AND ENGINE COMPONENTS
Springs – Design of helical springs – Design of Leaf, Belleville springs and Torsion springs – Flywheels considering stresses in rims and arms for engines and punching machines. Design of Crankshaft.
Spring is an elastic body whose function is to distort when loaded and to recover its original shape when the load is removed.
APPLICATION OF SPRINGS
To apply forces as in brakes, clutches and spring loaded valves.
To store energy as in watches, toys.
To measure forces as in spring balance and engine indicators.
To cushion, absorb or control energy due to either shock or vibration as in car.The material of the spring should have
high fatigue strength,
high ductility,
high resilience and
creep resistant.
It largely depends upon the size and service.
The strength of the wires varies with size, smaller size wires have greater strength and less ductility, due to the greater degree of cold working.
Severe service means rapid continuous loading where the ratio of minimum to maximum load (or stress) is one-half or less, as in automotive valve springs.
Average service includes the same stress range as in severe service but with only intermittent operation, as in engine governor springs and automobile suspension springs.
Light service includes springs subjected to loads that are static or very infrequently varied, as in safety valve springs.
The springs are mostly made from oil-tempered carbon steel wires containing 0.60 to 0.70 per cent carbon and 0.60 to 1.0 per cent manganese.
PPT On Spring Design , it is used in Machine Design for Engineering and At various Perpuses.
Compression springs are coil springs that resist a compressive force applied axially. Compression springs or coil springs have a spring constant and may be cylindrical springs, conical springs, tapered , concave or convex in shape. Compression springs are linear and thus have the same rate per inch throughout the entire spring. You can have large compression springs, heavy duty compression springs, conical compression spring, small compression springs, or even micro compression springs. Coil compression springs are wound in a helix usually out of round wire. The changing of compression spring ends, direction of the helix, material, and finish all allow a compression spring to meet a wide variety of special industrial needs. Coil springs can be manufactured to very tight tolerances, this allows the coil spring to precisely fit in a hole or around a shaft. A digital load tester, or coil spring compression tester can be used to accurately measure the specific load points in your metal spring. The possibilities are almost endless because there are so many applications for metal springs.
Compression springs can accomplish many types of applications such as pushing or twisting, thus allowing you to achieve numerous results. Compression springs offer resistance to linear compressing forces (push) and are in fact one of the most efficient energy storage devices available. A ballpoint pen is an excellent example of how small compression springs work. The small spring will compress when the pen is clicked and then the small spring will return to it's original position. Other uses include vibration dampening and high temperature applications.
Compression springs that are engineered for high temperature applications can reach up to 1,100 degrees Fahrenheit.
Review of Compression Helical Spring for Two Wheeler Suspension SystemsIJSRD
Present paper reviews the general study on configuration of helical springs. Fundamental of stress distribution and characteristics of helical coil spring has been reviewed. Discussion on parameters influencing the helical spring quality has also been explained. From the study it has been found that weight of the automobile helical spring should be reduced. So the springs are to be designed for higher stress and small dimensions. Finite element modelling brings improvement to the suspension spring analysis. A lot of study has been conducted on the Finite element analysis using ANSYS
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Welcome to WIPAC Monthly the magazine brought to you by the LinkedIn Group Water Industry Process Automation & Control.
In this month's edition, along with this month's industry news to celebrate the 13 years since the group was created we have articles including
A case study of the used of Advanced Process Control at the Wastewater Treatment works at Lleida in Spain
A look back on an article on smart wastewater networks in order to see how the industry has measured up in the interim around the adoption of Digital Transformation in the Water Industry.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
Forklift Classes Overview by Intella PartsIntella Parts
Discover the different forklift classes and their specific applications. Learn how to choose the right forklift for your needs to ensure safety, efficiency, and compliance in your operations.
For more technical information, visit our website https://intellaparts.com
The Internet of Things (IoT) is a revolutionary concept that connects everyday objects and devices to the internet, enabling them to communicate, collect, and exchange data. Imagine a world where your refrigerator notifies you when you’re running low on groceries, or streetlights adjust their brightness based on traffic patterns – that’s the power of IoT. In essence, IoT transforms ordinary objects into smart, interconnected devices, creating a network of endless possibilities.
Here is a blog on the role of electrical and electronics engineers in IOT. Let's dig in!!!!
For more such content visit: https://nttftrg.com/
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
Design of energy storing elements and engine components
1. D.M.E - B.B
1
DEPARTMENT OF MECHANICAL ENGINEERING
ME 6503 : DESIGN OF MACHINE ELEMENTS
UNIT -4 : DESIGN OF ENERGY STORING ELEMENTS AND ENGINE COMPONENTS
By
Mr. B.Balavairavan
Assistant Professor
Mechanical Engineering
Kamaraj College of Engg and Tech
Virudhunagar
2. Spring
Spring is an elastic body whose function is
to distort when loaded and to recover its
original shape when the load is removed.
Mechanical springs are
used in machines and other
applications mainly
• to exert force,
• to provide flexibility
• to store or absorb energy.
2D.M.E - B.B
3. Application of springs
1. To apply forces as in brakes, clutches and
spring loaded valves.
2. To store energy as in watches, toys.
3. To measure forces as in spring balance and
engine indicators.
4. To cushion, absorb or control energy due to
either shock or vibration as in car.
3D.M.E - B.B
4. The most common types of springs are as follows
1. Helical Spring
2. Leaf Spring
3. Disc Spring or Belleville Spring
Types of spring
4D.M.E - B.B
5. Types of spring – Helical spring
The helical springs are made up of a wire coiled in the
form of helix and are primarily intended for tensile or
compressive loads. The cross section of the wire from which
the spring made may be circular, square or rectangular. The
two forms of helical springs are compression spring and
helical tension springs.
Helical springs - Classification
a) Open coiled or Compression helical spring
b) Closed coiled or Tension helical spring
c) Torsion spring
d) Spiral spring
e) Concentric spring
5D.M.E - B.B
6. Types of spring – Helical spring
6D.M.E - B.B
(a) Open coiled or Compression helical spring
The springs which are sustain compressive force along the
axis are called compression helical or open coil springs. These
springs have helix angle more than 100
(b) Closed coiled or Tension helical spring
The springs which are sustain tensile force along the axis
are called tension helical or closed coil springs. These springs
have helix angle less than 100.
7. (c) Torsion Spring
It is also a form of helical spring, but it rotates about an
axis to create load. It releases the load in an arc around the
axis. Mainly used for torque transmission. The ends of the
spring are attached to other application objects, so that if the
object rotates around the center of the spring, it tends to push
the spring to retrieve its normal position.
D.M.E - B.B 7
Types of spring – Helical spring
8. Types of spring – Helical spring
(d) Spiral Spring
It is made of a band of steel wrapped around itself a
number of times to create a geometric shape. Its inner end is
attached to an arbor and outer end is attached to a retaining
drum. It has a few rotations and also contains a thicker band of
steel. It releases power when it unwinds.
D.M.E - B.B 8
9. Types of spring – Concentric spring
• Concentric helical springs are used to obtain a greater spring
force in a given space and to ensure the operation of a
mechanism in the event that one spring will break.
• To obtain the above conditions, either a two- spring nest or a
three-spring nest may be used.
• Fig. Shows the two concentric springs have the same free
length and arc compressed equally. Such springs are used for
automobile clutches and railway clutches.
D.M.E - B.B 9
11. Terminologies used in Helical spring
• Coil Diameter (D)
The mean diameter of the helix.
D = (D outer + Dinner)/2.
• Wire Diameter (d)
The diameter of the wire that is wound into a helix.
• Spring Index (C)
The ratio of mean coil diameter to wire diameter.
C = D/d
• Spring Stiffness or Spring rate (q)
The ratio of load required per unit deflection.
q = P/y
D.M.E - B.B 11
12. Terminologies used in Helical spring
• Active Coils (Na or n)
The number of coils which actually deform when the
spring is loaded.
• Inactive Coils
The coils which do not take part in deflection of the
spring are known as inactive coils.
• Total Coils (Nt)
The number of coils or turns in the spring.
D.M.E - B.B 12
13. Terminologies used in Helical spring
• Solid Length (La)
When the compression spring is compressed until the
coils come in contact with each other the spring is said to be
solid. The solid length of a spring is the product of total
number of coils and the diameter of the wire.
• Free Length (Lf)
It is the length of the spring in the free or unloaded
condition. It is equal to the solid length plus the maximum
deflection or compression of the spring and the clearance
between the adjacent coils.
D.M.E - B.B 13
14. End conditions of Helical spring
Generally, the following four end conditions are used.
1. Plain end
2. Plain and Ground
3. Squared end
4. Squared and Ground end
D.M.E - B.B 14
15. TERMINOLOGIES USED IN
HELICAL SPRING
• Pitch (p)
The pitch of the coil is defined as the axial distance
between any two adjacent coil in uncompressed state.
• Helix angle or Coil angle or pitch angle (α)
The angle between the coils and the base of the spring.
The pitch angle is calculated from the equation
D.M.E - B.B 15
16. Terminologies used in Helical spring
• Wahl’s Stress Concentration factor
A factor to correct stress in helical springs effects of
curvatures and direct shear.
D.M.E - B.B 16
17. Surge in Springs
• When one end of a helical spring is resting on a rigid support
and the other end is loaded suddenly, then all the coils of the
spring will not suddenly deflect equally, because some time is
required for the propagation of stress along the spring wire.
• If the applied load is of fluctuating type as in the case of valve
spring in internal combustion engines and if the time interval
between the load applications is equal to the time required for
the wave to travel from one end to the other end, then
resonance will occur.
• This results in very large deflections of the coils and
correspondingly very high stresses. Under these conditions, it
is just possible that the spring may fail. This phenomenon is
called surge. D.M.E - B.B 17
18. Surge in Springs
The surge in springs may be eliminated by using the following
methods :
1. By using friction dampers on the centre coils so that the wave
propagation dies out.
2. By using springs of high natural frequency.
3. By using springs having pitch of the coils near the ends
different than at the centre to have different natural
frequencies.
D.M.E - B.B 18
19. Buckling of springs
The helical compression spring behaves
like a column and buckles at a comparative
small load when the length of the spring is
more than 4 times the mean coil diameter.
Surge in springs
The material is subjected to higher stresses,
which may cause early fatigue failure. This
effect is called as spring surge.
D.M.E - B.B 19
20. Springs in series
• When two or more springs are arranged in
series and subjected to load P as shown in
figure.
• Their equivalent stiffness is given by
D.M.E - B.B 20
21. Springs in parallel
• When two or more springs are arranged in
parallel and subjected to load P as shown in
figure.
• Their equivalent stiffness is given by
q = q1 + q2
D.M.E - B.B 21
22. The laminated or leaf spring consists of a number of flat
plates of varying lengths held together by means of clamps and
bolts. These are mostly used in automobiles.
D.M.E - B.B 22
TYPES OF SPRING – Leaf Spring
23. Nipping in leaf spring
Stress in the full length leaves is 50% greater than the
stress in the graduated leaves. When the load is gradually
applied to the spring, the full length leaf is relieved of the
initial stress and then stressed in opposite direction. Such a pre
stressing obtained by a difference of radii of curvature is
known as nipping.
D.M.E - B.B 23
24. Materials for Leaf Springs
The material used for leaf springs is usually a plain carbon
steel having 0.90 to 1.0% carbon. The leaves are heat treated
after the forming process. The heat treatment of spring steel
produces greater strength and therefore greater load capacity,
greater range of deflection and better fatigue properties.
According to Indian standards, the recommended materials are
• 1. For automobiles : 50 Cr 1, 50 Cr 1 V 23, and 55 Si 2 Mn 90
all used in hardened and tempered state.
• 2. For rail road springs : C 55 (water-hardened), C 75 (oil-
hardened), 40 Si 2 Mn 90 (waterhardened) and 55 Si 2 Mn 90
(oil-hardened).
D.M.E - B.B 24
25. TYPES OF SPRING – Belleville
Spring
• Belleville springs or Disc springs are used where space
limitations require high capacity units i.e. Applications
requiring high spring stiffness and compact spring units. This
is obtained at the expense of thickly non-uniform stress
distribution across the section. High Stresses are used in the
design of Belleville springs. Each spring consists of several
annular discs that arc dished to a conical shape as in fig (a).
There are staked up one on top of another as in fig. (b) In order
to increase the deflection.
• The unit may be held in alignment by a central bolt or a tube.
The springs placed in series as shown in fig. (c) and the
deflection is proportional to the number of discs.
D.M.E - B.B 25
28. Flywheel
A flywheel used in machines serves as a
reservoir, which stores energy during the
period when the supply of energy is more than
the requirement, and releases it during the
period when the requirement of energy is more
than the supply.
D.M.E - B.B 28
29. Coefficient of Fluctuation of Speed
The difference between the maximum and
minimum speeds during a cycle is called the
maximum fluctuation of speed. The ratio of the
maximum fluctuation of speed to the mean speed is
called the coefficient of fluctuation of speed.
D.M.E - B.B 29
30. Turning moment diagram
The turning moment diagram (also known
as crank effort diagram) is the graphical
representation of the turning moment or crank-
effort for various positions of the crank. It is
plotted on cartesian co-ordinates, in which the
turning moment is taken as the ordinate and
crank angle as abscissa.
30D.M.E - B.B
34. Fluctuation of Energy
The variations of energy above and below the
mean resisting torque line are called fluctuations of
energy.
The difference between the maximum and the
minimum energies is known as maximum fluctuation
of energy.
Maximum fluctuation of energy, E =
Maximum energy – Minimum energy
34D.M.E - B.B
35. Coefficient of Fluctuation of Energy
It may be defined as the ratio of the
maximum fluctuation of energy to the work
done per cycle.
CE= Maximum fluctuation of energy /
Work done per cycle
35D.M.E - B.B
36. Work done per cycle
The work done per cycle (in N-m or joules)
may be obtained by using the following two
relations :
36D.M.E - B.B
38. Energy Stored in a Flywheel
Energy stored, E = mk2ω2CS = mv2CS
m = Mass of the flywheel in kg,
k = Radius of gyration of the flywheel in metres
ω = angular speed in rad/s2
Cs = Coefficient of Fluctuation of Speed
v = Mean linear velocity
D.M.E - B.B 38
39. Dimensions of the Flywheel Rim
Tensile stress or hoop stress,σ = ρR2ω2 = ρv2
ρ = Density of rim material in kg/m3,
N = Speed of the flywheel in r.p.m.,
ω = Angular velocity of the flywheel in rad/s,
v = Linear velocity at the mean radius in m/s
= ω R = DN/60
D.M.E - B.B 39
40. Mass of the rim, m = Volume × density = ρ DA
If the cross-section of the rim is a
rectangular, then
A = b × t
where b = Width of the rim, and
t = Thickness of the rim.
D.M.E - B.B 40
Dimensions of the Flywheel Rim